| Message ID | 20240522185924.461742-2-detlev.casanova@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: rockchip: vop2: Add VP clock resets support | expand |
Hi Detlev， At 2024-05-23 02:57:48, "Detlev Casanova" <detlev.casanova@collabora.com> wrote: >At the end of initialization, each VP clock needs to be reset before >they can be used. > >Failing to do so can put the VOP in an undefined state where the >generated HDMI signal is either lost or not matching the selected mode. Would you please provide a detailed description of your test case? > >Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> >--- > drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 30 ++++++++++++++++++++ > 1 file changed, 30 insertions(+) > >diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c >index fdd768bbd487c..e81a67161d29a 100644 >--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c >+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c >@@ -17,6 +17,7 @@ > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > #include <linux/regmap.h> >+#include <linux/reset.h> > #include <linux/swab.h> > > #include <drm/drm.h> >@@ -157,6 +158,7 @@ struct vop2_win { > struct vop2_video_port { > struct drm_crtc crtc; > struct vop2 *vop2; >+ struct reset_control *dclk_rst; > struct clk *dclk; > unsigned int id; > const struct vop2_video_port_data *data; >@@ -1915,6 +1917,26 @@ static int us_to_vertical_line(struct drm_display_mode *mode, int us) > return us * mode->clock / mode->htotal / 1000; > } > >+static int vop2_clk_reset(struct vop2_video_port *vp) >+{ >+ struct reset_control *rstc = vp->dclk_rst; >+ struct vop2 *vop2 = vp->vop2; >+ int ret; >+ >+ if (!rstc) >+ return 0; In fact, this check is not necessary here. The following reset control api will check for NULL pointer。 >+ >+ ret = reset_control_assert(rstc); >+ if (ret < 0) >+ drm_warn(vop2->drm, "failed to assert reset\n"); >+ udelay(10); >+ ret = reset_control_deassert(rstc); >+ if (ret < 0) >+ drm_warn(vop2->drm, "failed to deassert reset\n"); >+ >+ return ret; >+} >+ > static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, > struct drm_atomic_state *state) > { >@@ -2055,6 +2077,8 @@ static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, > > vop2_vp_write(vp, RK3568_VP_DSP_CTRL, dsp_ctrl); > >+ vop2_clk_reset(vp); >+ > drm_crtc_vblank_on(crtc); > > vop2_unlock(vop2); >@@ -2706,6 +2730,12 @@ static int vop2_create_crtcs(struct vop2 *vop2) > vp->data = vp_data; > > snprintf(dclk_name, sizeof(dclk_name), "dclk_vp%d", vp->id); >+ vp->dclk_rst = devm_reset_control_get_optional(vop2->dev, dclk_name); >+ if (IS_ERR(vp->dclk_rst)) { >+ drm_err(vop2->drm, "failed to get %s reset\n", dclk_name); >+ return PTR_ERR(vp->dclk_rst); >+ } >+ > vp->dclk = devm_clk_get(vop2->dev, dclk_name); > if (IS_ERR(vp->dclk)) { > drm_err(vop2->drm, "failed to get %s\n", dclk_name); >-- >2.44.1 > > >_______________________________________________ >linux-arm-kernel mailing list >linux-arm-kernel@lists.infradead.org >http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Thursday, 23 May 2024 23:09:26 EST Andy Yan wrote: > Hi Detlev， > > At 2024-05-23 02:57:48, "Detlev Casanova" <detlev.casanova@collabora.com> wrote: > >At the end of initialization, each VP clock needs to be reset before > >they can be used. > > > >Failing to do so can put the VOP in an undefined state where the > >generated HDMI signal is either lost or not matching the selected mode. > > Would you please provide a detailed description of your test case? The test case was to switch modes (using modetest) until the HDMI signal was lost on the TV side. It was also possible to detect the issue by tracking the HDMI TX Controller_VIDEO_MONITOR_STATUS[1-6] registers, especially at address 0x890, where the register would take the value `0x0000018c`. After adding these resets, the issue cannot be reproduced. I can share a script that reproduced this in the past (but this is an old patchset now, so things could have changed) > >Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> > >--- > > > > drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 30 ++++++++++++++++++++ > > 1 file changed, 30 insertions(+) > > > >diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c > >b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c index > >fdd768bbd487c..e81a67161d29a 100644 > >--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c > >+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c > >@@ -17,6 +17,7 @@ > > > > #include <linux/platform_device.h> > > #include <linux/pm_runtime.h> > > #include <linux/regmap.h> > > > >+#include <linux/reset.h> > > > > #include <linux/swab.h> > > > > #include <drm/drm.h> > > > >@@ -157,6 +158,7 @@ struct vop2_win { > > > > struct vop2_video_port { > > > > struct drm_crtc crtc; > > struct vop2 *vop2; > > > >+ struct reset_control *dclk_rst; > > > > struct clk *dclk; > > unsigned int id; > > const struct vop2_video_port_data *data; > > > >@@ -1915,6 +1917,26 @@ static int us_to_vertical_line(struct > >drm_display_mode *mode, int us)> > > return us * mode->clock / mode->htotal / 1000; > > > > } > > > >+static int vop2_clk_reset(struct vop2_video_port *vp) > >+{ > >+ struct reset_control *rstc = vp->dclk_rst; > >+ struct vop2 *vop2 = vp->vop2; > >+ int ret; > >+ > >+ if (!rstc) > >+ return 0; > > In fact, this check is not necessary here. The following reset control api > will check for NULL pointer Agreed, I'll do a rebased v3 and remove the check. > >+ > >+ ret = reset_control_assert(rstc); > >+ if (ret < 0) > >+ drm_warn(vop2->drm, "failed to assert reset\n"); > >+ udelay(10); > >+ ret = reset_control_deassert(rstc); > >+ if (ret < 0) > >+ drm_warn(vop2->drm, "failed to deassert reset\n"); > >+ > >+ return ret; > >+} > >+ > > > > static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, > > > > struct drm_atomic_state *state) > > > > { > > > >@@ -2055,6 +2077,8 @@ static void vop2_crtc_atomic_enable(struct drm_crtc > >*crtc,> > > vop2_vp_write(vp, RK3568_VP_DSP_CTRL, dsp_ctrl); > > > >+ vop2_clk_reset(vp); > >+ > > > > drm_crtc_vblank_on(crtc); > > > > vop2_unlock(vop2); > > > >@@ -2706,6 +2730,12 @@ static int vop2_create_crtcs(struct vop2 *vop2) > > > > vp->data = vp_data; > > > > snprintf(dclk_name, sizeof(dclk_name), "dclk_vp%d", vp- >id); > > > >+ vp->dclk_rst = devm_reset_control_get_optional(vop2- >dev, dclk_name); > >+ if (IS_ERR(vp->dclk_rst)) { > >+ drm_err(vop2->drm, "failed to get %s reset\n", dclk_name); > >+ return PTR_ERR(vp->dclk_rst); > >+ } > >+ > > > > vp->dclk = devm_clk_get(vop2->dev, dclk_name); > > if (IS_ERR(vp->dclk)) { > > > > drm_err(vop2->drm, "failed to get %s\n", dclk_name);
On Friday, 8 November 2024 11:39:57 EST Detlev Casanova wrote: > On Thursday, 23 May 2024 23:09:26 EST Andy Yan wrote: > > Hi Detlev， > > > > At 2024-05-23 02:57:48, "Detlev Casanova" <detlev.casanova@collabora.com> > > wrote: > > >At the end of initialization, each VP clock needs to be reset before > > >they can be used. > > > > > >Failing to do so can put the VOP in an undefined state where the > > >generated HDMI signal is either lost or not matching the selected mode. > > > > Would you please provide a detailed description of your test case? > > The test case was to switch modes (using modetest) until the HDMI signal was > lost on the TV side. It was also possible to detect the issue by tracking > the HDMI TX Controller_VIDEO_MONITOR_STATUS[1-6] registers, especially at > address 0x890, where the register would take the value `0x0000018c`. > > After adding these resets, the issue cannot be reproduced. I can share a > script that reproduced this in the past (but this is an old patchset now, so > things could have changed) > > > >Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> > > >--- > > > > > > drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 30 ++++++++++++++++++++ > > > 1 file changed, 30 insertions(+) > > > > > >diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c > > >b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c index > > >fdd768bbd487c..e81a67161d29a 100644 > > >--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c > > >+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c > > >@@ -17,6 +17,7 @@ > > > > > > #include <linux/platform_device.h> > > > #include <linux/pm_runtime.h> > > > #include <linux/regmap.h> > > > > > >+#include <linux/reset.h> > > > > > > #include <linux/swab.h> > > > > > > #include <drm/drm.h> > > > > > >@@ -157,6 +158,7 @@ struct vop2_win { > > > > > > struct vop2_video_port { > > > > > > struct drm_crtc crtc; > > > struct vop2 *vop2; > > > > > >+ struct reset_control *dclk_rst; > > > > > > struct clk *dclk; > > > unsigned int id; > > > const struct vop2_video_port_data *data; > > > > > >@@ -1915,6 +1917,26 @@ static int us_to_vertical_line(struct > > >drm_display_mode *mode, int us)> > > > > > > return us * mode->clock / mode->htotal / 1000; > > > > > > } > > > > > >+static int vop2_clk_reset(struct vop2_video_port *vp) > > >+{ > > >+ struct reset_control *rstc = vp->dclk_rst; > > >+ struct vop2 *vop2 = vp->vop2; > > >+ int ret; > > >+ > > >+ if (!rstc) > > >+ return 0; > > > > In fact, this check is not necessary here. The following reset control > > api > > will check for NULL pointer > > Agreed, I'll do a rebased v3 and remove the check. Actually, re-thinking about it, the check is done to avoid the udelay(10); if there is no resets configured, so I'd rather keep it that way. > > >+ > > >+ ret = reset_control_assert(rstc); > > >+ if (ret < 0) > > >+ drm_warn(vop2->drm, "failed to assert reset\n"); > > >+ udelay(10); > > >+ ret = reset_control_deassert(rstc); > > >+ if (ret < 0) > > >+ drm_warn(vop2->drm, "failed to deassert reset\n"); > > >+ > > >+ return ret; > > >+} > > >+ > > > > > > static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, > > > > > > struct drm_atomic_state > > *state) > > > > { > > > > > >@@ -2055,6 +2077,8 @@ static void vop2_crtc_atomic_enable(struct drm_crtc > > >*crtc,> > > > > > > vop2_vp_write(vp, RK3568_VP_DSP_CTRL, dsp_ctrl); > > > > > >+ vop2_clk_reset(vp); > > >+ > > > > > > drm_crtc_vblank_on(crtc); > > > > > > vop2_unlock(vop2); > > > > > >@@ -2706,6 +2730,12 @@ static int vop2_create_crtcs(struct vop2 *vop2) > > > > > > vp->data = vp_data; > > > > > > snprintf(dclk_name, sizeof(dclk_name), "dclk_vp%d", vp- > > > >id); > > > > >+ vp->dclk_rst = devm_reset_control_get_optional(vop2- > > > >dev, dclk_name); > > > > >+ if (IS_ERR(vp->dclk_rst)) { > > >+ drm_err(vop2->drm, "failed to get %s reset\n", > > dclk_name); > > > >+ return PTR_ERR(vp->dclk_rst); > > >+ } > > >+ > > > > > > vp->dclk = devm_clk_get(vop2->dev, dclk_name); > > > if (IS_ERR(vp->dclk)) { > > > > > > drm_err(vop2->drm, "failed to get %s\n", > > dclk_name);
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c index fdd768bbd487c..e81a67161d29a 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c @@ -17,6 +17,7 @@ #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/regmap.h> +#include <linux/reset.h> #include <linux/swab.h> #include <drm/drm.h> @@ -157,6 +158,7 @@ struct vop2_win { struct vop2_video_port { struct drm_crtc crtc; struct vop2 *vop2; + struct reset_control *dclk_rst; struct clk *dclk; unsigned int id; const struct vop2_video_port_data *data; @@ -1915,6 +1917,26 @@ static int us_to_vertical_line(struct drm_display_mode *mode, int us) return us * mode->clock / mode->htotal / 1000; } +static int vop2_clk_reset(struct vop2_video_port *vp) +{ + struct reset_control *rstc = vp->dclk_rst; + struct vop2 *vop2 = vp->vop2; + int ret; + + if (!rstc) + return 0; + + ret = reset_control_assert(rstc); + if (ret < 0) + drm_warn(vop2->drm, "failed to assert reset\n"); + udelay(10); + ret = reset_control_deassert(rstc); + if (ret < 0) + drm_warn(vop2->drm, "failed to deassert reset\n"); + + return ret; +} + static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, struct drm_atomic_state *state) { @@ -2055,6 +2077,8 @@ static void vop2_crtc_atomic_enable(struct drm_crtc *crtc, vop2_vp_write(vp, RK3568_VP_DSP_CTRL, dsp_ctrl); + vop2_clk_reset(vp); + drm_crtc_vblank_on(crtc); vop2_unlock(vop2); @@ -2706,6 +2730,12 @@ static int vop2_create_crtcs(struct vop2 *vop2) vp->data = vp_data; snprintf(dclk_name, sizeof(dclk_name), "dclk_vp%d", vp->id); + vp->dclk_rst = devm_reset_control_get_optional(vop2->dev, dclk_name); + if (IS_ERR(vp->dclk_rst)) { + drm_err(vop2->drm, "failed to get %s reset\n", dclk_name); + return PTR_ERR(vp->dclk_rst); + } + vp->dclk = devm_clk_get(vop2->dev, dclk_name); if (IS_ERR(vp->dclk)) { drm_err(vop2->drm, "failed to get %s\n", dclk_name);
At the end of initialization, each VP clock needs to be reset before they can be used. Failing to do so can put the VOP in an undefined state where the generated HDMI signal is either lost or not matching the selected mode. Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> --- drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 30 ++++++++++++++++++++ 1 file changed, 30 insertions(+)